I have designed an FIR filter which discards the high frequency noise. I have tested the functionality through simulation (MATLAB). Now I wish to quantify this, that how good is my system and get results which I can compare with existing literature. Can someone describe a few parameters (preferably with mathematical definition) on basis of which I can do this.
Dear Sudhanshu Janwadkar ,
Welcome!
The filters either analog or digital are characterized by a frequency transfer characteristics IH(exp jwTs)I , which can be obtained directly from H(z) with Z is the complex frequency transfer parameter where Z= exp jwTs.
Another method is to input a sinewave with known amplitude Vi and frequency and convert it into digital signal by sampling it and applying it to an A/D c onverter to digitize it and then apply it on the filter after which you convert the about digital out into analog signal .
Then measure the its peak value Vo. Then you can calculate the magnitude of the transfer characteristics IH(f)I= Vo/Vi, vary the frequency and keep the sampling frequency fs consatnt in the required range up to fs/2. Then Draw the transfer characteristics. You can see the cut-off frequency and the attenuation at high frequency.
Best wishes
Dear Dr Janwadkar:
The essential parameters of a filter are its cutoff frequency and its slope. The cutoff frequency is, basically, the demarcation between frequencies that the filter allows to pass, and frequencies that it tries to eliminate.
https://electronicmusic.fandom.com/wiki/Filter
Regards--
Dear Sudhanshu Janwadkar ,
Welcome!
The filters either analog or digital are characterized by a frequency transfer characteristics IH(exp jwTs)I , which can be obtained directly from H(z) with Z is the complex frequency transfer parameter where Z= exp jwTs.
Another method is to input a sinewave with known amplitude Vi and frequency and convert it into digital signal by sampling it and applying it to an A/D c onverter to digitize it and then apply it on the filter after which you convert the about digital out into analog signal .
Then measure the its peak value Vo. Then you can calculate the magnitude of the transfer characteristics IH(f)I= Vo/Vi, vary the frequency and keep the sampling frequency fs consatnt in the required range up to fs/2. Then Draw the transfer characteristics. You can see the cut-off frequency and the attenuation at high frequency.
Best wishes
Give us the coefficients of your filter and I will give you its frequency response.
Please read my work
Construction of The Sampled Signal Up To Any Frequency While Keeping The Sampling Rate Fixed
I hope you have a good idea.
If your application is to remove high frequency noise then the first quality criterion is the improvement in SNR (usually measured in dB).
So first create signal and noise with given powers so that you know the SNR, add them and filter them and estimate the SNR again.
Of course, this doesn't tell you if you have distorted your signal. How important this is and what kind of distortions are important, depend on the signal. If it's phase is important, then phase distortion of an AR or ARMA filter may be critical.
Y(J)S
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